Vitamin D deficiency in children and adolescents with type 1 diabetes

Objective: to investigate the frequency and effects of vitamin d deficiency in children with type 1 diabetes (t1d) in a region which is known to have a high rate of vitamin d deficiency among adolescents. methods: in this prospective cross-sectional study,120 children and adolescents with t1d (55 girls and 65 boys) aged 3-20 years were evaluated. serum 25-hydroxyvitamin d [25(oh)d],parathormone (pth),and alkaline phosphatase (alp) levels were measured. hemoglobin a1c levels and daily insulin requirement were also evaluated. classification of vitamin d status was made according to the american academy of pediatrics (aap)/lweps's recommendations. the patients were divided into 2 groups according to their vitamin d status and also according to the season of the year in which 25(oh)d sampling was done. results: serum 25(oh)d levels revealed vitamin d deficiency or insufficiency in 38% of the patients. higher pth levels were found in the patient group whose mean 25(oh)d level was <20 ng/ml as compared to the group whose mean 25(oh)d level was >20 ng/ml (p<0.05). only 11% of patients had secondary hyperparathyroidism. the 25(oh)d levels of patients whose serum samples were taken in summer and spring months were significantly different (p<0.05). there were no significant correlations between 25(oh)d level and daily insulin dose. conclusion: although we could not show a significant association between vitamin d deficiency and metabolic parameters,the frequency of vitamin d deficiency in t1d children is substantial. vitamin d status should be assessed also in patients who do not have signs of rickets. © journal of clinical research in pediatric endocrinology,published by galenos publishing.